St. Servaas (Servatius) is the patron saint of Maastricht. He was the bishop of Tongres (a Belgian city) who sought refuge behind the castellum walls of Maastricht from Germanic incursions. The bishop established a Christian community which became the Onze Lieve Vrouwekerk and the seat of the new diocese of Maastricht. When Servaas died, around the year 384, he was buried beside the Roman road outside the castellum. About 150 years later, Bishop Monulphus built a chapel on this site which was to grow into the church and chapter of St Servaas, the city's second greater church.  His tomb in the crypt has been a favored place of pilgrimage for many centuries. Famous visitors include Charlemagne and Pope John Paul II when he visited in 1985.